California Water Service - Bear Gulch District

Service Area

The Bear Gulch District is located in southern San Mateo County, and serves the communities of Atherton, Portola Valley, Woodside, parts of Menlo Park, parts of unincorporated Redwood City, and adjacent unincorporated portions of San Mateo County including: West Menlo Park, Ladera, North Fair Oaks, and Menlo Oaks.

Cal Water acquired the Los Trancos County Water District in 2005, and acquired both Skyline County Water District and Woodside Mutual Water Company in 2009, incorporating them into the Bear Gulch District. These systems serve rural communities along Highway 35 between Page Mill Road and Highway 92.

System

Note: Skyline system totals are included in the Profile and Summary numbers. Skyline’s portion of the total is shown in parentheses.

0.92 - Length of storage based on loss of all sources of supply. All zones can meet the 8 hr criteria either separately or by pumping from zones with excess capacity. Could increase use of Bear Gulch reservoir in an emergency to meet partial demand.

Summary

The Bear Gulch District receives 85% to 95% of its daily supply from the SF RWS, with the balance supplied by surface water runoff from California Water Service Company’s own watershed. The water is stored in the 215 million gallon Bear Gulch Reservoir, and treated at the 6 mgd Station 2 Filter Plant before distribution. The Skyline system is not hydraulically connected to the Bear Gulch system and receives 100% of its supply from the SF RWS. The Woodside Mutual system has been connected to the main Bear Gulch system for several years and has been served by Cal Water since this time.

The distribution systems consist of 57 pressure zones, 77 booster pumps, 35 storage tanks and reservoirs, 2,278 hydrants, and 289 miles of main. District water tanks provide storage for slightly more than 11 mg of potable water.

Water Supply and Demand

Supply by Source

Actual
FY 12-13
(ccf)

Actual
FY 13-14
(ccf)

Actual
FY 14-15
(ccf)

Actual
FY 15-16
(ccf)

San Francisco Water

5,814,767

6,259,793

5,077,292

3,864,869

Local Groundwater

0

0

0

0

Surface Water

301,395

0

190,342

329,563

Recycled Water

0

0

0

0

Other

0

0

0

0

Total

6,116,162

6,259,793

5,267,634

4,194,432

mgd equivalent

12.53

12.83

10.80

8.60

Demand by Sector

Residential

5,099,148

5,213,264

4,547,592

3,363,149

Commercial/Industrial

579,757

553,536

514,822

426,018

Other

156,803

166,553

123,349

101,350

Dedicated Irrigation

12,328

9,578

11,584

10,648

Unaccounted for

268,126

316,862

70,287

293,267

Total

6,116,162

6,259,793

5,267,634

4,194,432

mgd equivalent

12.53

12.83

10.80

8.60

Per Capita Use

Actual
FY 12-13
(gpcpd)

Actual
FY 13-14
(gpcpd)

Actual
FY 14-15
(gpcpd)

Actual
FY 15-16
(gpcpd)

Residential

180

180

156

115

Gross

216

220

180

144

Facilities and Distribution

Storage Reservoirs

Designation

Type

Capacity (gallons)

Designation

Type

Capacity (gallons)

Bear Gulch Reservoir*

Earth

215,000,000

Sta. 028-Tank 1

Steel

200,000

Sta. 002-Tank 1

Steel

250,000

Sta. 029-Tank 1

Fiberglass-Lined Redwood

100,000

Sta. 002-Tank 2

Steel

500,000

Sta. 029-Tank 2

Fiberglass-Lined Redwood

100,000

Sta. 005-Tank 6

Fiberglass-Lined Redwood

100,000 (inactive)

Sta. 029-Tank 3

Steel

150,000

Sta. 005-Tank 8

Steel

250,000

Sta. 030-Tank 1

Steel

1,000,000

Sta. 005-Tank 9

Steel

1,000,000

Sta. 031-Tank 2

Steel

165,000

Sta. 006-Tank 1

Steel

200,000

Sta. 032-Tank 1

Steel

250,000

Sta. 007-Tank 5

Fiberglass-Lined Redwood

100,000

Sta. 033-Tank 1

Steel

10,000

Sta. 015-Tank 1

Fiberglass-Lined Redwood

30,000

Sta. 034-Tank 1

Concrete

50,000

Sta. 016-Res.1

Steel

1,000,000

Sta. 036-Tank 1

Steel

125,000

Sta. 017-Tank 1

Steel

250,000

Sta. 037-Tank 1

Steel

55,000

Sta. 019-Tank 1

Steel

500,000

Sta. 038-Tank 1

Steel

212,000

Sta. 019-Tank 2

Steel

500,000

Sta. 039-Tank 1

Steel

282,000

Sta. 021-Tank 1

Steel

1,000,000

Sta. 041-Tank 1

Steel

189,000

Sta. 021-Tank 2

Steel

1,000,000

Sta. 041-Tank 2

Steel

192,000

Sta. 022-Tank 1

Steel

450,000

Sta. 042-Tank 1

Steel

60,000

Sta. 025-Tank 1

Fiberglass-Lined Redwood

100,000

Sta. 042-Tank 2

Steel

60,000

Sta. 027-Tank 4

Steel

750,000

Total

226,192,000

* Reservoir storage capacity has been reduced by 6 feet in compliance with DSOD
* requirements.